Print preview does not update when inserting fields

[helmut]

When printing, one can use EXIF, IPTC, and other placeholders. When using the "Insert" button to insert such a placeholder, the print preview does not refresh.

To reproduce:
1.) In XnView browser select an image.
2.) Select menu "File > Print".
3.) In Print dialog switch to tab "Header/Footer".
4.) Insert a field in header or footer field using the "Insert" button
--> Print preview is not updated

Updating works for the caption (tab "Caption"), so I consider this as a bug.

XnView 1.90.3